1. Field of Invention
The present invention relates to a method for manufacturing a carbon fiber rim, and in particular, to a method for manufacturing a carbon fiber rim with a brake layer formed by a thermosetting resin-based composite material.
2. Related Art
Bicycles on the market generally use two types of brake, i.e., caliper brake and disc brake. The bicycle brake system using the caliper brake is widely used because of its simple structure, light weight and low price; moreover, as the bicycle tends to be light-weighted in recent years, the traditional aluminum alloy material has been gradually replaced by a carbon fiber composite material, which is widely used because in addition to the advantage of light weight, the carbon fiber composite material has high strength and good shock absorption. However, as shown in FIG. 1, the carbon fiber bicycle rim not only needs to support the cyclist's weight and the bicycle's weight, but also needs to load up-to-down impact and left-to-right torsion brought about by various road conditions. When the bicycle travels along a long continuous steep downhill section, a decelerating or stopping effect is achieved by friction between the brake block and the rim. However, as it is difficult for the rim made of the carbon fiber composite material to dissipate heat, the rim continuously contacts and rubs against the brake block to generate heat during the braking, and relatively, heat may be accumulated on the rim, which may result in that the rim is easy to be scratched, cracked or deformed, or even cause the danger of rim breakage or brake failure when the heat cannot be dissipated rapidly.
To solve the above problem, the industry takes the following processing measures.
For example, in Taiwan Publication No. M389648 “BICYCLE COMPOSITE MATERIAL RIM HAVING PROTECTIVE COATING,” as shown in FIG. 2, the rim includes a metal frame 101 and a carbon fiber frame 102, two sides of the metal frame 101 each have a braking section 11 for contacting the brake block (not shown) of the bicycle brake system to generate friction, so as to make the moving bicycle slow down or stop. The braking section 11 forms a protective coating 20 by spraying metal powder to the surface of the braking section 11 with a spray process, thereby replacing the braking section 11 with the protective coating 20 to contact the brake block of the bicycle.
However, as the cost of the metal spray coating method is too high, the price of the bicycle does not have market competitiveness correspondingly, and the bicycle rim further includes a metal frame portion, which substantially has not been capable of thoroughly achieving the lightweight aim as compared with the rim completely made of the carbon fiber composite material.
Also, surface plating is applied to the braking section of the bicycle rim, so that the surface of the braking section has a plated metal layer, thereby achieving the decelerating or brake effect with the surface of the plated metal layer contacting and rubbing against the brake block of the bicycle. However, after the manner of being attached to the surface of the rim by means of metal coating has been used for a considerable time, the metal coating may peel off, and a lot of time or money needs to be spent on the maintenance and repair, which is not beneficial to the cost.